Stacker crane



11, 1964 R. VALLIERE ETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet l FIG] INVENTORS ROBERTL. VALLIERE Y WALTER A. PAULSSEN AT TORNEYS Aug. 11, 1964 R. L. VALLIEREETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet 2 INVENTORS ROBERT LVALLIERE WALTER A. FAULSSEN ATTORNEYS Aug. 11, 1964 R. L. VALLIERE ETAL3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet Z l I l 1 I INVENTORSH64 ROBERT L. VALLIERE Y WALTER A. PAULSSEN AT TO NEYS g- 11, 1964 R. L.VALLlERE ETAL 3,144,137

STACKER CRANE Filed Jan. 30, 1962 4 Sheets-Sheet 4 IN VEN TORS FIG. 5

WALTER A. FAULSSEN www kmw AT TO RNEYS ROBERT L. VALLIERE v UnitedStates Patent 3,144,137 STACKER CRANE Robert L. Valiiere, RooseveltPark, and Walter A. Paulssen, Spring Lake, Mich, assignors to Manning,Maxwell & Moore, Incorporated, Muskegon, MiClL, a corporation of NewJersey Filed Jan. 30, 1962, Ser. No. 169,872 8 Claims. (Cl. 212-128)This invention relates to improvements in a stacker crane, and moreparticularly to a stacker crane of the type highly desirable for use inwarehouses and other storage locations wherein materials of variouskinds are stored on vertically disposed shelving, racks or binassemblies and the like, the crane being utilized for order picking orselection as well as storage, although the invention will have otheruses and purposes as will be apparent to one skilled in the art. I

Stacker cranes of the general type of the instant invention usuallycomprise a mast depending from a trolley which traverses a travellingbridge spanning the area in which the crane operates. Drive means wereprovided to rotate the mast at least through one revolution. In someinstances the mast was a fixed mast and a load carrying assemblytravelled up and down the mast, while in other instances the mastcomprised telescopic sections, only the uppermost of which was fixed,and a load carrying assembly was mounted on the lower section. In eitherevent, the mast is subject to a bending moment, by virtue of the factthat the load is disposed to one side of the mast seated on a pair oflifting forks or other load holding means. Of course, the mast must beof suflicient strength and so mounted as to overcome this bendingmoment.

Cranes of this general type heretofore made have proven objectionableowing to their particular construction. Such cranes had the load liftingmachinery located on the mast itself, and frequently the means ormechanism for rotating the mast was also located on the mast. Sucharrangement resulted in an extremely congested area at the top of themast, and since all of the live load was initially carried by the mast,extremely heavy thrust bearings and related components had to be used atthe top of the mast where the mast connects with the trolley. Withstructures of this type as heretofore known, a mast with all themachinery located on it at the top thereof was most apt to be mounted onan underhung type or monorail trolley, since if it were connected with atop running trolley the bridge girders would necessarily be spreadobjectionably far apart in order to accommodate all of the machinerytherebetween. Locating most of the machinery within the frame of themast itself results in adversely affecting the available lifting power,while locating the machinery on the mast but outside of the framecreates a definite problem as to clearances. Obviously,

with the machinery located on the mast near the top thereof the heightto which a load may be lifted is necessarily reduced.

With the foregoing in mind, it is an important object of the instantinvention to provide a stacker crane having a trolley riding atravelling bridge with a mast depending from the trolley, and soconstructed that the entire live load is carried by the trolley andtransmitted directly to the bridge rails, the mast being subject only toa bending moment by virtue of the load being off the center line of themast.

Also an object of this invention is the provision of a stacker cranehaving a mast depending from a trolley that rides a travelling bridge,with all the hoisting machinery and mast rotating means being carried bythe trolley.

It is also an object of this invention to provide a stacker "ice cranehaving a mast depending from a movable trolley, the structure being suchthat the trolley may be of the underhung or top running type and yet thegirders of the travelling bridge on which the trolley rides may remainat the same distance apart regardless of which type of trolley isutilized.

It is also a feature of this invention to provide a stacker craneembodying a telescoping mast depending from a trolley riding atravelling bridge, and wherein all of the live load including thetelescoping mast sections is carried directly by the trolley asdistinguished from the mast.

Still another object of the instant invention is the provision of astacker crane embodying a rotary mast depending from a trolley with allof the lifting machinery mounted on the trolley and with the ropes fromthe hoisting drum extending downwardly through the central portion ofthe mast to a lower block which is mounted on a swivel to preventtwisting of the ropes about themselves when the mast is rotated.

It is also a desideratum of this invention to provide a stacker cranehaving a mast depending from a trolley with load engaging means on themast connected in a shock absorbing manner with the lift ropes dependingfrom a hoisting drum carried by the trolley.

A further feature of the instant invention is the provision of a stackercrane more economical, more versatile, and permitting a higher lift thanstacker cranes heretofore known.

While some of the more salient features, characteristics and advantagesof the instant invention have been above pointed out, others will becomeapparent from the following disclosures, taken in conjunction with theaccompanying drawings, in which:

FIGURE 1 is a fragmentary side elevational view of a stacker craneembodying principles of the instant inven tion, showing the sameassociated with a travelling bridge, parts being broken away and partsshown in section;

FIGURE 2 is a fragmentary vertical sectional view through the stackercrane taken substantially as indicated by the staggered section lineII-II of FIGURE 1, looking in the direction of the arrows;

FIGURE 3 is an enlarged fragmentary top plan view of the trolley of thecrane, taken from the right-hand side of FIGURE 2;

FIGURE 4 is an end view of the upper portion of the crane structure,with parts shown in section;

FIGURE 5 is a plan sectional view taken substantially as indicated bythe section line V-V of FIGURE 2; and

FIGURE 6 is an enlarged vertical sectional view, with parts omitted,taken substantially as indicated by the line VI-VI of FIGURE 5.

As Shown on the Drawings With reference now to FIGURES 1 and 2 of thedrawings, it will be seen that the illustrated embodiment of the instantinvention is shown by Way of example with a trolley of the top runningtype which traverses a bridge generally indicated by numeral 1 whichspans the area in which the stacker crane is to operate. Any suitableform of support may be provided for the ends of the bridge, as indicatedat 2-2, which supports each carry a rail 3 thereon upon which the bridgerides by means of wheels 4. The bridge embodies a frame structureincluding side girders 5-5, along one of which is provided a catwalk 6.On the top of each of the side girders 5--5 and extending lengthwisethereof is a rail 7 on which the trolley of the instant invention rides,as best seen in FIG- URE 4. At this point, it should be noted that withthe structure of the instant invention regardless of whether the trolleyis of the top running type as shown, or the underhung type, the girders5-5 of the bridge may be the same distance apart, it not being necessaryto increase the spacing between these girders to accommodate a toprunning trolley as embodied in the instant invention.

The trolley of this invention embodies a frame structure 8 fabricated inany suitable manner, and at each end of this frame structure is atransverse shaft 9 having a wheel 10 on each end thereof, which wheelsride the rails 7-7 on the aforesaid bridge 1. The shafts 9-9 arejournalled in suitable bearings as indicated at 11, and it will beunderstood that all of the shafts are journalled in adequate bearingswhich will not be fully described herein since they are of standard andknown form. The entire trolley traversing, mast rotating, and loadelevating machinery is carried on the trolley itself.

For traversing the trolley on the bridge rails 7-7, the trolley carriesan electric motor 12 which acts upon the end of one of the shafts 9through a gear case 13. Power for the motor 12 may be supplied by way ofa collector arrangement generally indicated by numeral 14 in FTG- URE 2,the particular electric circuit for energizing all of the motors notbeing a part of the instant invention, but may be of a known character.The motor 12 is, of course, reversible so that the trolley may move ineither direction along the bridge.

Also mounted upon the trolley is a hoist drum 15 around which the loadlifting rope is wound. This drum is driven by means of an electric motor16 acting through a transverse shaft 17, a gear box 18, and thence tothe shaft 19 of the drum itself. Adjacent the drum is a rope pulley 20the axis of which is disposed transversely to the drum axis, and thelifting rope is reeved over this pulley in a manner to be laterdescribed.

Also on the trolley is a mast rotating electric motor 21 which actsthrough a speed reducer 22 having a slip clutch, and on a dependingportion of the speed reducer a drive sprocket 23 is mounted.

It will be noted that the motors 12 and 16 and the gear box 18 projectlaterally beyond the sides of the frame of the trolley and extendlaterally over the bridge girders 5-5. If the trolley were mounted in anunderhung position on the bridge, this same apparatus would projectlaterally beneath the girders 5-5. Consequently there is no reason forchanging the distance between the bridge girders for either type oftrolley. On the other hand, if such mechanism was mounted on the top ofthe mast itself as has been done heretofore, the bridge girders wouldnecessarily have to be spaced farther apart for a top running trolleythan for an underhung trolley.

The trolley also carries means for suspending the mast therefrom whichare connected to an underhung portion 24 of the trolley frame, and thesemeans are best seen in FIGURE 4. A supporting ring 25 welded orequivalently secured to the frame portion 24 has bolted to the undersidethereof a bearing cage 26 and a bearing retainer 27 for a ball bearingassembly 28. A sprocket 29 is associated with the inner side of thebearing assembly 28, and a cylindrical member 30 is bolted by way of alaterally extending top flange 31 to the underside of the sprocket. Thiscylindrical member 39 has collector rings 32 on the outer side thereofassociated with a fixed collector member 33 associated in the necessaryelectrical circuits. As seen in FIGURE 2, the cylindrical member 30 hasan outwardly extending annular flange 34 on the lower end thereof forsupporting the mast. Trained over the sprocket 29 and the aforesaidsprocket 23 on the speed reducer 22 is a roller chain diagrammaticallyindicated at 35, and when the mast rotating motor 21 is operated ineither direction, the member 30 by way of its connection to the sprocket29 is rotated in the corresponding direction.

The mast itself comprises an upper section 36 the upper end of which iswelded or equivalently secured to the bottom flange 34 on thecylindrical member 30, an intermediate or second section 37, and a loweror load carrying section 38. These sections successively increase intransverse area downwardly and are telescopically arranged,

the two lower sections being movable relatively and conjointly, whilethe upper section is fixed. With reference to FIGURE 5, it will be seenthat the upper mast section 36 has the cross-sectional shape of an opensided rectangle, with a transverse flange 39 extending along each edgeof the open side. The second section 37 is similarly shaped, but isprovided with an inwardly extending flange 46 at each edge of the openside, which flanges 49 overlap the flanges 39 on the upper section. Thelower section 38 is similarly shaped, but along each edge of the openside there is an outwardly extending flange 41. In order to facilitatetelescoping of the mast sections, the upper section is provided onopposite ends thereof with external longitudinally extending ribs 42-42,and the secend section is provided with a pair of rollers 43 to engageeach rib 42 on opposite sides thereof. Likewise, the sec ond section 37is provided with opposed external ribs 44, and the lower section 38 isprovided with a pair of rollers 45 to act against each of these ribs. Asindicated in FIGURE 2, the second section may be provided with upper andlower pairs of rollers for each rib, if so desired, as many pairs ofrollers being used as may be deemed necessary tostabilize the structure.

The load engaging means are carried by the lower mast section 38, and inthe illustrated instance these means are in the form of a pair of liftforks, adjustable as to the space therebetween. The load engagingassembly includes an upper pair of brackets 46-46 and a similar lowerpair of brackets 47-47 welded or equivalently secured to the opposedflanges 41-41 on the lower mast section, as best seen in FIGURES 2, 5and 6. The upper brackets 46-46 carry a fixed sleeve 48 therein and thelower brackets 47-47 carry a fixed sleeve 49 therein. Rotatably mountedin suitable bearings 50-50 secured to the flanges 41-41 of the lowermast section is a tubular shaft 51 having one end externally threadedwith right-hand threads as indicated at 52, and the opposite endexternally threaded with left-hand threads as indicated at 53. Asprocket 54 is keyed to this shaft, which sprocket is driven by a chaindiagrammatically indicated at 55 in FIGURE 5 from a sprocket 56 on aspeed reducer 57 actuated by an electric motor 58. The motor and speedreducer are mounted on a suitable bracket 59 attached to the lower mastsection in any suitable manner.

A pair of lifting fork asemblies, generally indicated by numerals 60 and61 are provided, and these are arranged allochirally but otherwise areidentical in structure. Each such assembly includes an uprightsupporting member 62 having upper and lower stationary shafts 63 and 64extending inwardly therefrom into telescopic engagement with theaforesaid tubes 48 and 49. Centrally thereof the supporting member 62 isprovided with a drive nut 65 in engagement with the threads on therespective end of the shaft 51. At the lower end hereof, the supportingmember 62 carries a horizontally extending lift fork 66. Actuation ofthe motor 58, which is a reversible motor, causes the supporting members62 of the lifting forks to be moved inwardly or outwardly as desired tovary the distance between the two lift forks 66-66, whereby the forksare enabled to adequately support loads of various sizes.

Secured centrally to the .fixed sleeves 48 and 49 is a supporting member67 having an inwardly extending portion 68 which supports a known typeof load cell 69 which automatically gives the weight of any load on thelift forks 66-66. The load cell is disposed in the space within the mastsection and is suspended from a lower block 70 by means of a bolt 71.The bolt extends into a cylinder 72 on the load cell 69, which cylinderis closed by a cover 73 and between that cover and a washer 74 at thelower end of the bolt is a compression spring 75, whereby the entireload on the lift forks is carried by the spring 75 so that accurateweight of the load can be obtained and indicated by the load cell.Beneath the head of the bolt inside the block 70 and below the washer74, bearings 76 and 77 are provided respectively so that the load mayrotate relatively to the block 70. Within the block 70 is a pair ofsheaves 78 and 79.

With reference to FIGURE 2 it will be seen that the lift rope 80 hasboth ends anchored to the hoist drum on the trolley in spacedrelationship as indicated at 81 and 82. From the anchor point 81, therope extends downwardly inside the mast sections around the sheave 78,then upwardly and over the sheave on the trolley, downwardly around thesheave 79, and back to the anchor point 82. When the mast is rotated,the lower block 70 remains in the same position by virtue of the swivelconnection established by the bolt 71 between this block and the loadcell, and consequently the reaches of the lift rope within the mast arenot twisted about themselves. Adequate tension on the rope isestablished by the dead weight of the load engaging assembly, when noload is on the forks.

An operators cab or cage 83 is suspended by an in verted L-shapedbracket 84 having the upper end thereof bolted or equivalently securedas indicated at 85 to the upper end of the intermediate mast section 37,as seen in FIGURE 1. This manner of mounting the operators cage keepsthe cage spaced outwardly from the mast so that the lower section of themast may rise above the cage to the position seen in FIGURE 1, wherebythe height of lift for a load is not limited by the operators cage orthe operator himself, and the operator is never in danger of strikinghis head on some portion of the upper structure. This arrangementpermits a higher lift by the instant invention than was possible withstacker cranes heretofore made.

It will be understood that adequate safety features, such as automaticbraking means in case of rope failure, limit switches, and the likewhich are of a known character may be installed as desired on theinstant stacker crane.

In operation, the instant invention is extremely simple, positive, andeffective. The trolley is caused to traverse the bridge until the liftforks are in a position to pick up a load, and the mast is rotated inorder to adequately engage that load, if necessary. When the hoist drumis operated the lower section of the mast is elevated until the top ofit strikes an abutment 86 on the top of the intermediate section 37, andthen the intermediate section is carried along with the lower section towhatever height may be desired, or to the highest possible point shownin FIGURE 1. The mast itself is subject only to a bending moment sincethe mast does not carry the load, nor does the mast have thereon any ofthe elevating machinery which is entirely carried by the trolley. Theload is automatically weighed when lifted by the forks, the load may beelevated above the operators cab, the mast and load rotated wheneverdesired without danger of twisting the reaches of the lift rope andoperation of the crane for elevating or lowering loads is accomplishedwith rapidity and accuracy.

It will be understood that modifications and variations may be eifectedwithout departing from the scope of the novel concepts of the presentinvention.

What we claim as our invention:

1. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality of hollowtelescoping sections,

load engaging means on the lower section of said mast,

a hoist drum on said trolley,

a lift rope between said drum and said load engaging means and extendingthrough the sections of said mast, and

actuating means for said hoist drum also carried by said trolley.

2. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley, said mast comprising a plurality ofhollow telescoping sections of which the upper is the smallest incross-section and the lower is the largest,

load engaging means carried by the lower mast section and extendingthereinto,

a hoist drum on said trolley,

a rope from said drum extending downwardly through the mast sections,

a lower block on said rope inside the lower mast section,

a swivel connection between said block and the extending portion of saidload engaging means, and

actuating means for said hoist drum carried by said trolley.

3. In a stacker crane,

a traveling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality of hollowtelescoping sections,

load engaging means on the lower part of said mast extending inside saidmast,

a hoist means on said trolley,

a rope from said hoist means extending through said mast,

and a swivel connection between said rope and said load engaging meansinside said mast.

4. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a hollow mast depending from said trolley,

load engaging means on the lower part of said mast,

a load cell connected to said means inside said mast for automaticweighing of a load on said means,

hoisting means on said trolley,

and a rope extending through said mast and connecting said hoistingmeans and said load cell inside said mast.

5. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality oftelescopic sections,

load engaging means connected to the lower section of said mast,

an operators cab connected to the top of the next above mast section andspaced from said mast to permit the lower mast section and load engagingmeans to rise above said cab, and

hoisting means to elevate said load engaging means and telescope saidmast.

6. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley and comprising a plurality oftelescopic sections,

load engaging means connected to the lower section of said mast,

a bracket connected to the top of the next above section extendingoutwardly therefrom and downwardly spaced from said mast,

an operators cab suspended from said bracket to one side of said mast topermit the load engaging means on the lower mast section to rise abovesaid cab, and

hoisting means carried by said trolley to elevate said load engagingmeans and telescope said mast.

7. In a stacker crane,

a travelling bridge,

a trolley to traverse said bridge,

a mast depending from said trolley,

7 8 load engaging means on the lower part of said mast, means connectingsaid swivel to said load cell by way hoisting means on said trolley, ofsaid compression spring. a rope depending from said hoisting means, andShock absorbing means disposed between and COII- References Cited in thefile of this patent nected to said rope and said load engaging means. 5

8. In a stacker crane, UNITED STATES PATENTS a travelling bridge,951,304 Clark et a1. Mar. 8, 1910 a trolley to traverse said bridge,1,697,538 Moore Jan. 1, 1929 a mast depending from said trolley,2,847,131 Miller Aug. 12, 1958 load engaging means on the lower part ofsaid mast, 10 2,933,198 Firestone et a1. Apr. 19, 1960 hoisting means onsaid ey, 2,947,426 Cotesworth et a1. Aug. 2, 1960 a rope depending fromsaid hoisting means, 2 932 425 Moore May 2 1961 a block on the lowerpart of said rope,

a swivel on said block, FOREIGN PATENTS a load cell connected to saidload engaging means, 15 05 903 Germany Apr. 4 1957 a compression spring,and

1. IN A STACKER CRANE, A TRAVELLING BRIDGE, A TROLLEY TO TRANSVERSE SAID BRIDGE, A MAST DEPENDING FROM SAID TROLLEY AND COMPRISING A PLURALITY OF HOLLOW TELESCOPING SECTIONS, LOAD ENGAGING MEANS ON THE LOWER SECTION OF SAID MAST, A HOIST DRUM ON SAID TROLLEY, A LIFT ROPE BETWEEN SAID DRUM AND SAID LOAD ENGAGING MEANS AND EXTENDING THROUGH THE SECTIONS OF SAID MAST, AND 